Impediment in lathe chzjoks



L, VON GUNTEN.

` Lathe Chuck.

' Patented Dec. 4, 1866.

fw TMs-5555..'

@uiten V,tate-s @anni fifi.

IMPROWMENT 1N LATHE timers.

sPEGHIFIC es''cxer-l TO ALL WHOMIT MAY CONOERN: A i

v Be it known that I, LOUIS'VON GUNTEN, of CincinnatLVHamilton county, Ohio, have invented-new andi useful Watchmakers Lathe Chuck; and I do hereby declare the following to be a full, clear, and' exact descrip` i tion thereof, reference bein g had' to the accompanyingrdrawings, making part-ofthis` specification.

My invention relates to a -form of lathe chuck adapted for accurately and rmlygrasping watch pinionl and arbors, and other minute objects. i J

Figure 1 is a perspective view of my chuck, with the mandrel detached` Figure 2 is an axial section through the same.

The spindle A has the customaryl tail or point B and journal C. It is also 'providedlwitha suitable driving.` ,j j

pulley, D, which may have the represented conical and stepped form, in orderrto obtain diierent speeds from 'the i. same belt. Journaled axially within the spindle A is a nut E, having a milled head e, to which access is a'orded` l by scollops a in the sides of thespindle. All that part of the spindle which includes and is in front oi' the nut is chamberedout to receive and hold a mandrel, F, composed of `spring steel. The extreme forward portion of this chamber consists of `a daring mouthrG, tot the daring head H of the mandrel; and said mouth communij. cat cs rearward with a cylindrical chamber I, which fits 4and encloses corresponding collars J J 0n the mandrel shank. The shank of the mandrel terminates in a screw K, which ts the nut E.` The Haring head Hof my mandral has two narrow'slits or kerfs, L, which. divide the head into ifour` precisely similar and diametrically" opposite jaws h. In their normal or unrestrained condition, the jaws h assume, of themselves, the gapingforgn shown in the drawing. A short distance in rear of their front end the jawsh4 are chambered out, as shown in iig. 2, so as .to receive Withinl them, without injury, a pinion o'r other enlargement, when desired. The ap'exes of the jaws are scolloped out, so as to form, collectively, a cylindrical throat'l, -When itis desired Vto secure or chuck a piece of work, one end of it is inserted "in the throat l, and the nutE being rotated, the twopairs of i f opposite jaws close simultaneously and equally upon the work, so as to hold the same rmly and accurately central. The collars I J and cylindricall chamber I retain the mandrel to a strictlyaxial position, with every variety of adjustment, j Several mandrels of diverse calibers of throats being provided, enables 4the chucking., i

of either largevor very minute objects.

I claim herein as new and of my invention- The grasping jaws h h h L, formed upon a stem F, guided by collars .I J", and 'operated by a.' nut E e core.` j j fined within the chambered spindle A, which is formed with scollops a 11,10 afford access to the milled-head e of i .the nut, all constructed and combined, substantially as herein described, and for the purposes specified.

' In testimony of which invention Ihereunto setmy hand. j i` LOUIS VON GUNTEN.

Witnesses: i

Guo. H. KNIGHT, JAMES H. LAYMAN. 

